Solar Energy

Scott Cummings, Chemistry, Kenyon College


Solar Energy (CHEM 108) is a one-semester chemistry lecture and discussion course designed for students majoring outside of the natural sciences. With an emphasis on quantitative reasoning, the course explores the chemical principles associated with societal fossil-fuel use (and associated environmental problems) and solar-energy technologies that could offer sustainable solutions.

Course Size:

Course Format:
Lecture only

Institution Type:
Private four-year institution, primarily undergraduate

Course Context:

This course has no pre-requisites and does not serve as a pre-requisite for further study in chemistry. It was designed as one of the "non-majors" offerings from the Chemistry Department to serve as a path for students to fulfill their natural science distribution requirement, and nearly all of the students enrolled in CHEM 108 major in a discipline outside of the natural sciences. In addition, the course was designed as a way for students to complete another graduation requirement: one course in quantitative reasoning (QR); approximately half of all the students enroll in CHEM 108 to satisfy the QR requirement. Finally, Solar Energy was designed to serve as one of the required courses for the Environmental Studies interdisciplinary minor, and approximately 20-30% of the students enroll in CHEM 108 for this reason.

Course Content:

Solar Energy explores the chemistry of fossil fuels and alternatives such as solar electricity and solar fuels. Students learn chemical principles of reaction stoichiometry, molecular structure, thermochemistry, catalysis, energy quantization, and electrochemistry in the context of investigating solar radiation, combustion, greenhouse gases, ethanol, photovoltaics, water electrolysis, fuel cells, hydrogen storage, and batteries. With regard to geoscience, we explore "peak oil" theory, models for solar radiation and planetary energy balance, and the effect of carbon dioxide emissions on global climate.

Course Goals:

Course design emphasizes: (1) depth in students' engagement with chemistry concepts related to the challenges of continued dependence on fossil fuels and the potential for renewable energy systems; (2) the use of quantitative reasoning to solve problems and critical thinking to evaluate claims; and (3) interdisciplinary connections with economics, politics, ecology and human health. My goal is to help students better understand the enormous challenges and the potentially transformative solutions, build connections between basic science and their personal interests, and feel empowered to make more informed choices or to advocate for change.

Course Features:

Consistent with the goals of the course, many exercises in class and on homework and exams emphasize how to "fact-check" claims using quantitative reasoning. The emphasis is on using general problem-solving techniques (unit-conversion / dimensional analysis), recognizing estimations and uncertainty, and then considering if calculations support or refute a claim.

Course Philosophy:

The course was initially designed with two mutual goals: to offer students an option for fulfilling the (new) QR requirement with a chemistry course, and to offer—for me and students—an opportunity to explore in more depth the issues of sustainability and chemistry.


Students are assigned weekly readings and problems sets (not graded). Evaluation combines frequent low-stakes grading of weekly online quizzes and in-class quizzes with two mid-term exams and a final exam that weigh heavily on the course grade. I strive to encouraging students to learn from their mistakes and synthesize their knowledge from various topics, so frequently repeat homework and quiz questions on exams. The timed nature of in-class assessment posses a significant challenge for many students, but I maintain that this type of assessment has value.


CHEM 108 syllabus 2012 (Acrobat (PDF) 266kB Jul2 12)

References and Notes:

(1) Chemistry in Context 7th edition; (2) Energy, Environment, and Climate by Richard Wolfson; (previously) Out of Gas: the End of the Age of Oil by David Goodstein
several Scientific American articles on peak oil, biofuels, and solar energy.